Genetically Modified Foods

Genetically Modified Foods:

Genetically Modified Foods Submitted to : Dr. H.B. Patel Dept of pharmacology Submitted by : Fotariya Milind H. Reg. no. :02-00135-06 Roll no. :07

What are GM and Bt foods? :

What are GM and Bt foods? GM stands for genetically modified . Plants of certain crops like soyabean, corn, cotton, sugar-beet and many others can be tweaked by scientists so that they develop desired properties like pest resistance or higher nutritional content . This tweaking is done through small changes in their genetic code - the DNA. Hence , they are called genetically modified (or engineered) crops . Food products made from such GM crops, like cornflakes from GM maize, are called GM foods.

Slide 3:

Bt cotton and Bt brinjal are a particular type of GM food - the Bt is actually derived from a soil bacterium called bacillus thuriengiensis (Bt). The gene introduced in cotton and brinjal is from that source.

How is genetic modification done? :

How is genetic modification done? All the properties of a living entity are encoded in its DNA, which is contained in the nuclei of its cells. The DNA is a long, double-stranded molecule with its constituents arranged in a particular order. Segments of this DNA, called genes, perform specific functions like making a protein or regulating a chemical process.

Slide 5:

Genetic scientists can find out which gene is performing what function. Research showed, for example , that Bt has a gene that directs the production of a protein, which is toxic to certain larvae (bugs). These bugs called bollworms and fruit & shoot borers are the main destroyers of cotton and brinjal. This gene was taken out of the bacteria and introduced into the cotton or brinjal plant's DNA. This genetically modified cell is allowed to grow into a plant and its seeds contain the code for pest resistance . When bollworms start eating plants grown from these seeds they die, saving the crop.

GM crops are being grown in the world today :

GM crops are being grown in the world today Since the introduction of the first GM seeds in 1996, their use has spread to 25 countries in the world, covering about 125 million hectares of land . In India, about 7.6 million hectares is under GM crops, mostly under Bt cotton. Long-lasting tomatoes : were the first genetically modified food available to consumers.

Slide 7:

Herbicide-tolerant soyabean : More than half of the GM crop area is under herbicide-tolerant soyabean (65.8 mha). Insecticide sweet corn : ( Bt-corn) that produces a poison which kills harmful insects. Golden rice : contains a large amount of the element beta-carotene which is converted in the body into Vitamin-A . Maize, Sugar-beet, Bt cotton, Bt brinjal etc .

Advantages of GM foods:

Advantages of GM foods Pest resistance Herbicide tolerance Disease resistance Cold tolerance Drought tolerance Nutrition Pharmaceuticals

Disadvantage :

Disadvantage Unintended harm to other organisms : pollen from Bt corn caused high mortality rates in monarch butterfly caterpillars. Reduced effectiveness of pesticides: Gene transfer to non-target species : the transfer of the herbicide resistance genes from the crops into the weeds leads to "superweeds“ that are resistant herbicide.

Human health risks:

Human health risks Allergenicity Bt toxin is consistently associated with immune and allergic-type responses Indian farm workers exposed to Bt cotton developed moderate or severe allergic reactions Cancer and Degenerative Diseases

Animal health risks:

Animal health risks Sterility in thousands of cows or pigs Sheep that grazed on Bt-cotton plants exhibited nasal discharge, reddish and erosive mouth lesions, cough, bloat, diarrhea, and occasional red-colored urine with25% mortality. Deaths among cows , water buffalo , horses , and chickens .

Thank you:

Thank you